Hilmer Mathias, Peters Jürgen, Schulz Michael, Gruber Sebastian, Vorhauer Nicole, Tsotsas Evangelos, Foerst Petra
Institute of Process Systems Engineering, Technical University of Munich, Gregor-Mendel Straße 4, 85354 Freising, Germany.
Heinz Maier-Leibnitz Zentrum, Technical University of Munich, Lichtenbergstraße 1, 85748 Garching bei München, Germany.
Rev Sci Instrum. 2020 Jan 1;91(1):014102. doi: 10.1063/1.5126927.
This article shows a new conceptional design of an experimental setup for in situ visualization of the lyophilization process using neutron radiography and computed tomography and its validation. The setup is designed for the neutron imaging beam line ANTARES at FRM II, considering all the requirements for this method. Neutrons are ideally suited to detect water in a sample because of the high neutron attenuation of hydrogen, whereas other materials like aluminum have a low absorption of neutrons resulting in an image where the drying fronts in bulk materials are observable. Consisting of a freeze-drying cell and a sample-stick, the setup is basically inspired by a common freeze-drying unit. The cell is axial symmetrical to allow computed tomography measurements. The developed sample stick connects the vacuum cell with the measurement devices and the vacuum pump. Experiments were performed at FRM II, showing that the setup is functional. In addition, the experiments discovered some possibilities for improvements, which can be used in further measurements.
本文展示了一种用于利用中子射线照相术和计算机断层扫描对冻干过程进行原位可视化的实验装置的全新概念设计及其验证。该装置是为德国慕尼黑工业大学的FRM II的中子成像束线ANTARES设计的，考虑到了这种方法的所有要求。由于氢对中子的高衰减，中子非常适合检测样品中的水，而铝等其他材料对中子的吸收较低，从而形成一幅能够观察到块状材料干燥前沿的图像。该装置由一个冻干单元和一个样品棒组成，其基本灵感来自于普通的冻干设备。该单元是轴对称的，以允许进行计算机断层扫描测量。所开发的样品棒将真空单元与测量设备和真空泵连接起来。在FRM II进行了实验，结果表明该装置是可行的。此外，实验还发现了一些改进的可能性，可用于进一步的测量。
